/Engine/Source/Runtime/Core/Public/Containers/ContainerAllocationPolicies.h
These should be replaced with actual typedefs when Core.h include order is sorted out, as then we won't need to 'forward' theseTAllocatorTraitsspecializations below.
template<int IndexSize> class TSizedDefaultAllocator : public [TSizedHeapAllocator< IndexSize >](API\Runtime\Core\Containers\TSizedHeapAllocator)